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United States Patent | 5,299,938 |
Waltho | April 5, 1994 |
An apparatus for illustrating the operation of an Archimedes screw. Two passages (8,9) are defined which together form a single closed loop passageway. A first passage (8) is generally linear and a second passage (9) is of helical form and is connected at its ends to the ends of the first passage. The walls of the two passages are transparent such that the movement of fluid (10) can be clearly seen. The first and second passages are arranged such that if the first passage (8) is positioned at a predetermined inclination to the vertical fluid can be transferred through the second passage (9) from the lower to the upper end of the first passage by rotating the apparatus about an axis extending parallel to the length of the first passage. The second passage (9) may be in the form of a helical tube wound around the outside of a straight tube defining the first passage (8) .
Inventors: | Waltho; Barry S. (14 Primrose Cottages, Altrincham WA14 3EL, GB2) |
Appl. No.: | 941033 |
Filed: | September 30, 1992 |
PCT Filed: | January 31, 1991 |
PCT NO: | PCT/GB91/00145 |
371 Date: | September 30, 1992 |
102(e) Date: | September 30, 1992 |
PCT PUB.NO.: | WO91/11793 |
PCT PUB. Date: | August 8, 1991 |
Feb 01, 1990[GB] | 9002232 | |
May 31, 1990[GB] | 9012140 |
Current U.S. Class: | 434/126; 434/283 |
Intern'l Class: | G09B 009/00 |
Field of Search: | 434/283,302,300,126 472/68,67,57 446/267,167 |
2714260 | Aug., 1955 | Burckhardt | 434/283. |
2752725 | Jul., 1956 | Unsworth | 446/166. |
2871617 | Feb., 1959 | West | 446/267. |
4595369 | Jun., 1986 | Downs | 434/302. |
4778430 | Oct., 1988 | Goldfarb et al. | 446/167. |
Foreign Patent Documents | |||
2598471 | May., 1986 | FR. | |
0473583 | May., 1968 | CH. |